Servlet实现文件上传到服务器(不用表单,直接用代码模拟表单提交)

/**
* etao.test FileUpload.java 2014年4月20日
*/
package etao.autotest.report;

/**
* @author 东海陈光剑
* 2014年4月20日 下午5:03:58
*/

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class FileUpload {

/**
* 发送请求
*
* @param url
* 请求地址
* @param filePath
* 文件路径
* @return
* @throws IOException
*/
public synchronized String send(String url, String filePath)
throws IOException {

File file = new File(filePath);
if (!file.exists() || !file.isFile()) {
return "ERROR";
}

/**
* 第一部分
*/
URL urlObj = new URL(url);
HttpURLConnection con = (HttpURLConnection) urlObj.openConnection();

/**
* 设置关键值
*/
con.setRequestMethod("POST"); // 以Post方式提交表单，默认get方式
con.setDoInput(true);
con.setDoOutput(true);
con.setUseCaches(false); // post方式不能使用缓存

// 设置请求头信息
con.setRequestProperty("Connection", "Keep-Alive");
con.setRequestProperty("Charset", "UTF-8");

// 设置边界
String BOUNDARY = "----------" + System.currentTimeMillis();
con.setRequestProperty("Content-Type", "multipart/form-data; boundary="
+ BOUNDARY);

// 请求正文信息

// 第一部分：
StringBuilder sb = new StringBuilder();
sb.append("--"); // ////////必须多两道线
sb.append(BOUNDARY);
sb.append("\r\n");
sb.append("Content-Disposition: form-data;name=\"file\";filename=\""
+ file.getName() + "\"\r\n");
sb.append("Content-Type:application/octet-stream\r\n\r\n");

byte[] head = sb.toString().getBytes("utf-8");

// 获得输出流

OutputStream out = new DataOutputStream(con.getOutputStream());
out.write(head);

// 文件正文部分
DataInputStream in = new DataInputStream(new FileInputStream(file));
int bytes = 0;
byte[] bufferOut = new byte[1024];
while ((bytes = in.read(bufferOut)) != -1) {
out.write(bufferOut, 0, bytes);
}
in.close();

// 结尾部分
byte[] foot = ("\r\n--" + BOUNDARY + "--\r\n").getBytes("utf-8");// 定义最后数据分隔线

out.write(foot);

out.flush();
out.close();

/**
* 读取服务器响应，必须读取,否则提交不成功
*/

return " Upload | " + filePath + " | " + con.getResponseCode() + " | "
+ con.getResponseMessage();

/**
* 下面的方式读取也是可以的
*/

// try {
// // 定义BufferedReader输入流来读取URL的响应
// BufferedReader reader = new BufferedReader(new InputStreamReader(
// con.getInputStream()));
// String line = null;
// while ((line = reader.readLine()) != null) {
// System.out.println(line);
// }
// } catch (Exception e) {
// System.out.println("发送POST请求出现异常！" + e);
// e.printStackTrace();
// }

}

public static void main(String[] args) throws IOException {
FileUpload up = new FileUpload();
for (int i = 1; i <= 22; i++) {
System.out.println(up.send(
"http://127.0.0.1:8888/UploadServlet/upload",
"D:\\AAAATEMP\\img\\W (" + i + ").jpg"));
}
}
}

"http://127.0.0.1:8888/UploadServlet/upload" Sevlet实现代码:

/** * Upload.java etao.test.fileload UploadFileToServer 下午1:38:59 2014年4月20日 2014 */package etao.test.fileload;
/** * @author 东海陈光剑 * 2014年4月20日 下午1:38:59 */import java.io.File;import java.io.IOException;import java.util.Iterator;import java.util.List;
import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;import org.apache.commons.fileupload.disk.DiskFileItemFactory;import org.apache.commons.fileupload.servlet.ServletFileUpload;
@SuppressWarnings("serial")public class Upload extends HttpServlet { private String uploadPath = "C:\\autoTest\\httpd\\htdocs\\img"; // 上传文件的目录 private String tempPath = "c:\\buffer\\"; // 临时文件目录 File tempPathFile;
@SuppressWarnings("unchecked") public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { try { // Create a factory for disk-based file items DiskFileItemFactory factory = new DiskFileItemFactory();
// Set factory constraints factory.setSizeThreshold(4096); // 设置缓冲区大小，这里是4kb factory.setRepository(tempPathFile);// 设置缓冲区目录
// Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory);
// Set overall request size constraint upload.setSizeMax(4194304); // 设置最大文件尺寸，这里是4MB
List<FileItem> items = upload.parseRequest(request);// 得到所有的文件 Iterator<FileItem> i = items.iterator(); while (i.hasNext()) { FileItem fi = (FileItem) i.next(); String fileName = fi.getName(); if (fileName != null) { File fullFile = new File(fi.getName()); File savedFile = new File(uploadPath, fullFile.getName()); fi.write(savedFile); } System.out.println(fileName + " upload successfully!"); } // System.out.println("upload succeed"); } catch (Exception e) { // 可以跳转出错页面 e.printStackTrace(); } }
public void init() throws ServletException { File uploadFile = new File(uploadPath); if (!uploadFile.exists()) { uploadFile.mkdirs(); } File tempPathFile = new File(tempPath); if (!tempPathFile.exists()) { tempPathFile.mkdirs(); } }}
来源： <https://github.com/universsky/UploadServlet/blob/master/src/etao/test/fileload/Upload.java>

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